At times, the word "have" means "possess". We also use "have" to express the idea of obligation. We say that someone "has to do" something. In Spanish, when we use "have" to express obligation, we use the "R" form of the other verb but we also insert the word "que". The word "que" normally means "that", but in this case, it is just used to indicate that "have" means "have to do" not "have something".

Yo tengo que estudiar.
I have to study.

¿Tienes que estudiar?
Do you have to study?

Los muchachos tienen que estudiar.
The boys have to study.

Nosotros tenemos que estudiar.
We have to study.

Yo tengo que aprender las palabras.
I have to learn the words.

Tú tienes que aprender las palabras para el examen.
You have to learn the words for the test.

El profesor dice que nosotros tenemos que aprender las palabras para el examen.
The teacher says that we have to learn the words for the test.

Los muchachos tienen que aprender las palabras para el examen.
The boys have to learn the words for the test.

Los muchachos van a aprender las palabras para el examen.
The boys are going to learn the words for the test.

Los muchachos van a tener que aprender las palabras para el examen.
The boys are going to have to learn the words for the test.

Yo voy a aprender las palabras para el examen.
I am going to learn the words for the test.

Yo tengo que aprender las palabras para el examen.
I have to learn the words for the test.

Yo voy a tener que aprender las palabras para el examen.
I am going to have to learn the words for the test.

We know that we can use "have" for possession, but also for "obligation". We can say that someone "has" something, but also we can say that someone "has to do" something. In this case we have to insert the word "que" and follow it with the "R" form of the verb that tells us what someone has to do.

Yo tengo que estudiar.
I have to study.

If we use a pronoun direct object, we will have to put it in front of the entire verb phrase. In Spanish you can never split a verb phrase.

Yo tengo que estudiar el capítulo.
I have to study the chapter.

Yo lo tengo que estudiar.
I have to study it.

Yo tengo que estudiar el capítulo.
I have to study the chapter.

Yo lo tengo que estudiar.
I have to study it.

¿ Tienes que estudiar el capítulo?
Do you have to study the chapter?

¿ Lo tienes que estudiar?
Do you have to study it?

¿ Tienes que estudiar los capítulos?
Do you have to study the chapters?

¿ Los tienes que estudiar?
Do you have to study them?

Juan tiene que estudiar el capitulo.
John has to study the chapter.

Juan lo tiene que estudiar.
John has to study it.

Juan tiene que estudiar los capítulos.
John has to study the chapters.